Pyxidicula operculata, xlii, 88.f
— globata, xlii, 88.
Pyxidicula, xlii, 88.f
Raphoneis, characters of genus, xlviii, 204.
Sceptroneis, genus, xlviii, 326.f
Schizonema, xliii, 328.
Spherastrum, xli, 290.
Staurastrum paradoxum, xli, 289.
Stephanogonia, genus, xlviii, 326.f
Stephanopyxis, sub-genus, xlviii, 327.